pressure washer problems

[bob_wood]

This is an unloader valve. :Yours may look a little different, and may cost less.

Northern Tool + Equipment | Error


Pressure Washer Unloader Valve

Some GREAT reading for a guy with a pressure washer problem Thanks !!

bob

 

[J_J]

Bob,


You can probably take it apart , but you need to know some things. The most important is the max pump pressure. You can note the number of threads showing on the adjuster, and reset it to that position, or get a pressure gage and set the pressure to unload before it hits max pressure. You might call the manufacture of the pressure washer and he might tell you the relief setting. If you are going to take it apart, check the shaft of the unloader valve and the spring, and the seat for rust or corrosion.

The best thing probably is to replace the unloader. If you have a pressure washer shop in your area, they will sell you a valve, or they can install it for you.

Since you said the engine runs fine, and the pump is putting out water, It almost has to be the unloader valve. Make sure your gun and the tip are not clogged. Trying starting it with the gun unplugged.

I still have a lot of my commercial pressure washer stuff, just about one of everything that was available, and sometimes two or three of each. The best thing they ever came out with is the turbo nozzle. and the surface cleaners.

 

[bob_wood]

Bob,


You can probably take it apart , but you need to know some things. The most important is the max pump pressure. You can note the number of threads showing on the adjuster, and reset it to that position, or get a pressure gage and set the pressure to unload before it hits max pressure. You might call the manufacture of the pressure washer and he might tell you the relief setting. If you are going to take it apart, check the shaft of the unloader valve and the spring, and the seat for rust or corrosion.

The best thing probably is to replace the unloader. If you have a pressure washer shop in your area, they will sell you a valve, or they can install it for you.

Since you said the engine runs fine, and the pump is putting out water, It almost has to be the unloader valve. Make sure your gun and the tip are not clogged. Trying starting it with the gun unplugged.

I still have a lot of my commercial pressure washer stuff, just about one of everything that was available, and sometimes two or three of each. The best thing they ever came out with is the turbo nozzle. and the surface cleaners.

I took the unloader valve apart and discovered some damage. There is a part that looks somewhat like a needle valve. It rests against a ball bearing. The " needle valve tip was bent and disfigured. I called Northern Tool and ordered a new unloader valve. we'll see ... I'm pretty sure the unloader valve is my problem. Thanks again for all the help J_J

Bob

 

[bob_wood]

I installed a brand new unloader valve and now I get a very low pressure spray for a few seconds then the engine dies. I adjusted the pressure knob on the unloader but it doesnt make any difference. Any way I can verify that the pump is working properly ?

Bob

 

[J_J]

Make sure you have good input water pressure . Check the inlet filter. Check and see how much water is coming out the pump with hose disconnected. Disconnect the pump from the engine, and run the engine for a while. If the engine funs good, then the problem is in the pump. If you have a pressure gage that you can plug into the pump, that will tell you if it is putting out good pressure. If the pump is putting out good pressure, the relief/unloader valve will bypass or relieve if the gun trigger is off.

 

[J_J]

I unhooked the pump from the engine and the engine seems to run fine but the pump load is somehow killing the engine. Guess I should be troubleshooting this problem with the pump hooked to the engine. With the pump hooked up, I do see the choke lever go to full choke when the engine stalls.. any idea what That means? Does it on its own. Thanks for the input Tom

bob

The choke lever on that Honda is only to start the engine, and after starting, it does not move. Maybe you have the choke lever in the on position, which will and try to kill the engine.

 

[bob_wood]

Make sure you have good input water pressure . Check the inlet filter. Check and see how much water is coming out the pump with hose disconnected. Disconnect the pump from the engine, and run the engine for a while. If the engine funs good, then the problem is in the pump. If you have a pressure gage that you can plug into the pump, that will tell you if it is putting out good pressure. If the pump is putting out good pressure, the relief/unloader valve will bypass or relieve if the gun trigger is off.

I checked the inlet filter and it looks clean. The engine runs good when it is disconnected from the pump. When I disconnect the wand hose from the unloader valve, I get water thru the input filter and out the unloader , low pressure ( probably just going thru the bypass hose). The engine will stall in this configuration too so guess my wand and hose are not clogged. I dont have a pressure gauge. My engine choke is only on to start the engine. I'm going to work on it some more this morning. Might have to take this thing to somebody that knows more about it than I do . Thanks for the input J_J.

Bob

 

[ampsucker]

i believe that engine has a demand type govener? it definitely works harder when pumping under pressure than when free spinning with no load. i'm starting to suspect a clogged carb jet or as previously mentioned a gunked up fuel shut off valve or fuel filter. it sounds like the engine only dies under load when it is getting the request from the govener for more fuel.

any way to load the engine while the pump is disconnected?

amp

 

[bob_wood]

i believe that engine has a demand type govener? it definitely works harder when pumping under pressure than when free spinning with no load. i'm starting to suspect a clogged carb jet or as previously mentioned a gunked up fuel shut off valve or fuel filter. it sounds like the engine only dies under load when it is getting the request from the govener for more fuel.

any way to load the engine while the pump is disconnected?

amp

That Does make alotta sense to me amp. The engine ran when i disconnected it from the pump but it seemed to be a little rough. You got me thinkin now. Dont know how i could put a load on it off hand but thanks for that idea. Wish I could get this thing going , I need it. All my equipment is real dirty. When the engine runs ( with pump on it ) it goes up to full rpm, stays there for a few seconds... then its like ya flipped the off switch, it dosent bogg down at all, it just dies.
Bob

 

[ampsucker]

my honda pw has a governer arm that attaches to the carb linkage by a series of springs. i think it is internally demand actuated. if yours has this, you might try manually activating it with your finger to see if the motor can run at max rpm without the pump attached.

passing this test should eliminate any clogged high speed orifices inside the carb or a clogged fuel line as your problem. it might be running ok at idle or mid rpm, but starve for gas at WOT (wide open throttle).

doing this test is the equivalent of revving an engine with accelerator pedal only pressure washers don't a "throttle" per se, since they are designed to run at single rpm all the time. the governer manages the fuel to meet the demand and hold the engine at the correct rpm to produce the oem pressure and flow specs for the pump. you can trick it by pushing the governer arm with your finger to open up the carb.

there may also be an adjustment set screw on the governer arm that could be out of adjustment. if it passes the WOT test, you might try experimenting with that setting. if, for example, you put a load on the engine and the govener arm does NOT respond properly, the engine would die because it's not getting enough fuel to power the load. adjusting could help this or the internal workings of the govener could be messed up or gummed up and a good disassembly and cleaning might help if you diagnose that to be your problem.

amp